This invention relates to devices adapted for use with band saws and other saws having tables associated therewith for accurately cutting work pieces and, more particularly, to a device adapted to position the center of an arc to be cut in a work piece in order to cut the arc extremely accurately and precisely in all types of work pieces both large and small.
When cutting sheet stock and other work pieces on a band saw, circular table saw, or the like, it is often very difficult to guide the work piece in order to accurately cut the arc of a circle therein. The problem is accentuated with both extremely large and extremely small work pieces. With large work pieces, the piece extends off the typically small work support table provided with the saw and therefore must be simultaneously supported in a single plane in order to cut the edge at the required angle as well as rotated in a precise path in order to properly cut the circle or arc of a circle therein. With thicker sheet metal, the simultaneous performance of both of these actions is often impossible to accomplish with one saw operator. The necessity of additional help greatly increases the expense of cutting such pieces.
A related problem exists with extremely small work pieces in which arcs having extremely large radii must be cut. Although a smaller work piece can normally be supported by the existing work support table of the saw, it is extremely difficult to obtain an accurate, even cut along such a large radius arc merely by manually guiding the work piece against the cutting blade.
Various devices have been proposed to alleviate such problems of cutting arcs. Although some are secured to the work support table of the saw and include a screw or pin impressed into the work piece and about which the work piece is rotated against the cutting blade, a principal problem with these devices is their inability to sufficiently accommodate both extremely large and extremely small work pieces. Typically, support structure included with the apparatus prevents the cutting of larger pieces. Moreover, many of the structures require the center of the work piece be held against the existing work support table of the saw thereby severely limiting the size of the work piece which can be cut and providing an unstable support for those pieces which can be accommodated.